Well if you have time to kill and are curious take apart your rack. But at 37 years old and in this field for some time I have never worked anywhere (private garage or dealership) that serviced rack & pinions. I don't even know if you could buy the internal components retail over the counter. Anywhere I've worked it's simply take out old, flush system, install new. I could rebuild brake calipers too but why would I when I can buy loaded rebuilt ones for almost nothing for most cars. Now a rack costs a bit more than a brake caliper but my opinion on something like this is - buy it, install it, be done with it! Just my opinion .